/**
 * Copyright (c) 2021-2022 Huawei Device Co., Ltd.
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include "js_array_iterator.h"
#include "plugins/ecmascript/runtime/base/typed_array_helper-inl.h"
#include "plugins/ecmascript/runtime/base/typed_array_helper.h"
#include "global_env.h"
#include "js_array.h"
#include "object_factory.h"

namespace ark::ecmascript {
// 22.1.5.2.1 %ArrayIteratorPrototype%.next ( )
JSTaggedValue JSArrayIterator::Next(EcmaRuntimeCallInfo *argv)
{
    ASSERT(argv);
    JSThread *thread = argv->GetThread();
    [[maybe_unused]] EcmaHandleScope handleScope(thread);
    // 1.Let O be the this value.
    JSHandle<JSTaggedValue> input(builtins_common::GetThis(argv));

    // 2.If Type(O) is not Object, throw a TypeError exception.
    // 3.If O does not have all of the internal slots of an TaggedArray Iterator Instance (22.1.5.3), throw a TypeError
    // exception.
    if (!input->IsJSArrayIterator()) {
        THROW_TYPE_ERROR_AND_RETURN(thread, "this value is not an array iterator", JSTaggedValue::Exception());
    }
    JSHandle<JSArrayIterator> iter(input);
    // 4.Let a be O.[[IteratedArrayLike]].
    JSHandle<JSTaggedValue> array(thread, iter->GetIteratedArray());
    JSHandle<JSTaggedValue> undefinedHandle(thread, JSTaggedValue::Undefined());
    // 5.If a is undefined, return CreateIterResultObject(undefined, true).
    if (array->IsUndefined()) {
        return JSIterator::CreateIterResultObject(thread, undefinedHandle, true).GetTaggedValue();
    }
    // 6.Let index be O.[[ArrayLikeNextIndex]].
    uint32_t index = iter->GetNextIndex().GetInt();
    // 7.Let itemKind be O.[[ArrayLikeIterationKind]].
    IterationKind itemKind = IterationKind(iter->GetIterationKind().GetInt());

    uint32_t length;
    // 8. If a has a [[TypedArrayName]] internal slot, then
    //   a. Let len be the value of O’s [[ArrayLength]] internal slot.
    if (array->IsTypedArray()) {
        length = base::TypedArrayHelper::GetArrayLength(thread, JSHandle<JSObject>(array));
    } else {
        // 9.Else
        JSHandle<JSTaggedValue> lengthKey = thread->GlobalConstants()->GetHandledLengthString();
        JSHandle<JSTaggedValue> taggedLen = JSTaggedValue::GetProperty(thread, array, lengthKey).GetValue();
        if (UNLIKELY(!taggedLen->IsNumber())) {
            return JSIterator::CreateIterResultObject(thread, undefinedHandle, true).GetTaggedValue();
        }
        length = taggedLen->GetArrayLength();
        RETURN_EXCEPTION_IF_ABRUPT_COMPLETION(thread);
    }

    // 10.If index ≥ len, then
    if (index >= length) {
        // Set O.[[IteratedArrayLike]] to undefined.
        // Return CreateIterResultObject(undefined, true).
        iter->SetIteratedArray(thread, undefinedHandle);
        return JSIterator::CreateIterResultObject(thread, undefinedHandle, true).GetTaggedValue();
    }
    // 11.Set O.[[ArrayLikeNextIndex]] to index + 1.
    iter->SetNextIndex(thread, JSTaggedValue(index + 1));
    // 12.If itemKind is key, return CreateIterResultObject(index, false).
    JSHandle<JSTaggedValue> key(thread, JSTaggedValue(index));
    if (itemKind == IterationKind::KEY) {
        return JSIterator::CreateIterResultObject(thread, key, false).GetTaggedValue();
    }
    JSHandle<JSTaggedValue> sKey(JSTaggedValue::ToString(thread, key));
    JSHandle<JSTaggedValue> value = JSTaggedValue::GetProperty(thread, array, sKey).GetValue();
    RETURN_EXCEPTION_IF_ABRUPT_COMPLETION(thread);
    // 15.If itemKind is value, let result be elementValue.
    if (itemKind == IterationKind::VALUE) {
        return JSIterator::CreateIterResultObject(thread, value, false).GetTaggedValue();
    }
    // 16. Else
    ASSERT_PRINT(itemKind == IterationKind::KEY_AND_VALUE, "itemKind is invalid");
    ObjectFactory *factory = thread->GetEcmaVM()->GetFactory();
    JSHandle<TaggedArray> resultArray(factory->NewTaggedArray(2));  // 2 means the length of array
    resultArray->Set(thread, 0, key);
    resultArray->Set(thread, 1, value);
    JSHandle<JSTaggedValue> keyAndValue(JSArray::CreateArrayFromList(thread, resultArray));
    return JSIterator::CreateIterResultObject(thread, keyAndValue, false).GetTaggedValue();
}
}  // namespace ark::ecmascript
